Vehicular transmission pump drives

ABSTRACT

A VEHICULAR TRANSMISSION HAVING A HYDRAULIC PUMP DRIVEN BY THE TRANSMISSION INPUT THROUGH A ONE-WAY DRIVE WHEN THE IMPUT IS POWERING THE TRANSMISSION AND DRIVEN BY THE TRANSMISSION OUTPUT THROUGH A ONE-WAY DRIVE WHEN THE OUTPUT IS POWERING THE TRANSMISSION.   D R A W I N G

2 Sheets-Sheet 1 Jan. 16, 1973 E. N. COLE VEHICULAR TRANSMISSTON PUMPDRIVES Original Filed July 2. 1969 ATTORNEY Jun. 16, 1973 N. COLE Re.27,5 53

VEHICULAR TRANSMISSION PUMP DRIVES Original Filed July 2, 1969 2Sheets-Sheet 2 I N VEN TOR.

ATTORNEY United States Patent Oflice Reissued Jan. 16, 1973 VEHICULARTRANSMISSION PUMP DRIVES Edward N. Cole, Bloomfield Hills, Mich.,assignor to General Motors Corporation, Detroit, Mich.

Original No. 3,554,056, dated Jan. 12, 1971, Ser. No.

838,549, July 2, 1969. Application for reissue Aug.

26, 1971, Ser. No. 175,413

Int. Cl. F16h 47/00, 47/04, 47/08 US. Cl. 74-730 2 Claims Matterenclosed in heavy brackets appears in the original patent but forms nopart of this reissue specification; matter printed in italics indicatesthe additions made by reissue.

ABSTRACT OF THE DISCLOSURE A vehicular transmission having a hydraulicpump driven by the transmission input through a one-way drive when theinput is powering the transmission and driven by the transmission outputthrough a one-way drive when the output is powering the transmission.

This invention relates to vehicular transmissions and more particularlyto vehicular transmission pump drives.

In vehicular transmissions having an engine powered hydrodynamic torqueconverter which in turn powers range gearing, it is conventionalpractice to have a single hydraulic pump in the transmissioncontinuously driven by the engine via the pump transmission input forsupplying hydraulic pressure to the transmissions converter and controlsystem. It is also conventional practice to have an additional pumpdriven from the transmission output and thus capable of being driven bythe vehicles driving wheels so that pressure is available when theengine is not running and the vehicle is in motion. It is especiallyadvantageous to have this auxiliary pressure source when the pump supplyis used as a pressure source for what is commonly called a centralhydraulic system where, in addition to the pressure source serving thetransmission, it also serves other hydraulically operated vehicularequipment such as power steering, a brake booster, an antilock brakesystem, windshield wiper motors, power window motors, powerseatadjusters, a suspension leveling system, etc. Thus, when the enginedriven pump is not in operation, such as when the engine is not runningand provided the vehicle is in motion, pressure supply is available tooperate the various hydraulically operated vehicular equipment.

Where an auxiliary pump driven by vehicle motion is added to provide anauxiliary hydraulic pressure source, there is considerable added cost inaddition to the engineering and manufacturing problems presented inattempting to provide a compact arrangement, bearing in mind that it isadvantageous to have these pumps share the same reservoir. I have foundthat the advantages of such a two-pump arrangement are gained by havinga single pump which is driven by the transmission input and thus theengine when the input is powering the transmission and is driven by thetransmission output when the output and thus the vehicles driving Wheelsare powering the transmission.

The preferred embodiment of the present invention is illustrated in avehicular transmission comprising a hydrodynamic torque converterpowered by the engine driven transmission input. The converter normallypowers gearing which is operable to selectively establish differentspeed ratio drives between the converter and the transmission output. Asingle hydraulic pump providing a single hydraulic pressure source isarranged between the converter and the gearing. Drive is available tothe hydraulic pump through either one of two separate drives.

One of these pump drives is provided by a series arranged one-way clutchand gear drive between the input driven converter housing and thehydraulic pump so that the pump is driven by the transmission input whenthe engine is powering the transmission. The other pump drive is anauxiliary drive for providing drive from the transmission output to thepump. This auxiliary drive is provided by a series arranged one-wayclutch and gear drive between the converter output which is the input tothe transmission gearing and the hydraulic pump. This auxiliary driveprovides for the hydraulic pump being driven by the transmission outputwhen the vehicles driving wheels are powering the transmission gearingwith any one of the transmissions drives engaged.

An object of the present invention is to provide a new and improvedvehicular transmission pump drive arrangement.

Another object is to provide in a vehicular transmission a hydraulicpump which is driven by the transmission input when the input ispowering the transmission and driven by the transmission output when theoutput is powering the transmission.

Another object is to provide in a vehicular transmission having ahydrodynamic torque converter and gearing, a single hydraulic pump whichis arranged between the converter and gearing and is driven by thetransmission input when the input is powering the transmission and isdriven by the transmission output when the output is powering thetransmission.

Another object is to provide in a vehicular transmission a hydraulicpump having a one-way drive from both the transmission input and thetransmission output.

Another object is to provide in a vehicular transmission having atransmission input driven hydrodynamic torque converter powering gearingwhich is operable to establish different gear ratio drives between theconverter and the transmission ouput, a hydraulic pump having a one-waydrive from both the transmission input and the converter input to thegearing.

These and other objects of the present invention will be more apparentfrom the following description and drawing in which:

FIG. 1 is a longitudinal sectional view of a vehicular transmissionembodying the pump drives of the present invention.

FIG. 2 is an enlarged view of the pump drives shown in FIG. 1.

FIG. 3 is a view taken on line 3--3 of FIG. 2.

Referring to the drawing, FIG. 1 illustrates the invention in avehicular transmission generally comprising a hydrodynamic torqueconverter 10 and planetary type range gearing 11 housed in atransmission housing 12. This converter and range gearing arrangement isoperable to provide two forward speed range drives and a reverse speedrange drive with the pump drives according to the present inventionproviding for powering a hydraulic pump 14 when the transmission inputis powering the transmission and also when the transmission output ispowering the transmission with one of the transmission drives engaged.

Describing first the transmission drive train arrangement, input to thetransmission is delivered via a flange 15 which has provisions for beingconnected via a flywheel to the crankshaft of the vehicles engine.Flange 15 is welded to a drum 16 which acts as a container for converter10. The drum 16 carries a plurality of blades 18 providing theconverters impeller. The impeller blades 18 pump fluid to a plurality ofblades 19 providing the converters turbine, the turbine blades beingcarried by a shell 20. A plurality of blades 21 located between theexits of turbine blades 19 and entrances of impeller blades 18 arecarried by a hub 22 and provide the converters stator. A one-way brake24 has its outer race orcam member 25 secured to stator hub 22 and hasits inner race member 26 splined to a stationary sleeve shaft 28, thesleeve shaft 28 being made stationary by connection to the transmissionhousing 12 as described in more detail later. The oneway brake 24permits free rotation of the stator in the same direction as theimpeller and thus the engine crankshaft which direction will be calledthe forward direction and prevents reverse rotation of the stator. Theconverter, being a three element torque converter of the conventionaldesign, provides torque multiplication up to the converters couplingpoint and fluid coupling operation thereafter.

Input to range gearing 12 is from the converters turbine whose shell issplined to the forward end of a turbine or converter output shaft 30.The converter output shaft 30 extends freely through stationary shaft 28to the range gearing where it is splined to a sun gear 31. Sun gear 31meshes with a long pinion 32 which meshes with a short pinion 34. Thelong pinion 32 and short pinion 34 are mounted for rotation on pinionshafts 36 and 38, respectively, which are fixed to a carrier 39. Carrier39 is integral wtih the transmissions output shaft 41 which is journaledin the rear end 42 of the transmission housing, the rear end ofconverter output shaft 30 being piloted in the forward end of outputshaft 41. The short pinion 34 meshes with an annular sun gear 43 throughwhich the converter output shaft 30 freely extends. Sun gear 43 issplined to the hub of a plate 44 which is splined at its outer radius toa drum 45. The drum 45 is supported for rotation on a sleeve 46 having aflange 47 secured by bolts 48 to the transmission housing 12. The drum45 and connected sun gear 43 may be braked by engagement of ahydraulically operated band brake 49.

A clutch 50 operable to clutch the sun gear 43 to the range gearinginput comprises a clutch hub 51 which is splined to the converter outputshaft 30. A plurality of friction plates 52 with alternate platessplined to clutch hub 51 and intermediate plates splined to drum 45 areadapted to be engaged to provide the clutch connection. The frictionplates 52 are engaged by a hydraulic motor comprising a piston 53 whichforms with drum 45 a motor chamber 54 adapted to receive fluid. Releasesprings 56 seated at one end on a spring seat 57 mounted on drum 45 andat the other end on piston 53 normally biases the piston towards itsclutch release position shown. When hydraulic pressure is admitted tochamber 54 the piston 53 advances to engage the clutch.

The short pinion 34 mesh with a ring gear 60 which may be held by abrake 61. The brake 61 comprises a plurality of friction plates 62,alternate plates being splined to transmission housing 12 andintermediate plates being splined to ring gear 60. A hydraulic motoradapted to engage plates 62 comprises a piston 64 which forms with thetransmission housings rear end 42' a motor chamber 66 adapted to receivefluid. Release springs 68 seated at one end on a spring seat 69 carriedon the transmission housings rear end 42 and seated at the other end onpiston 64 biases the piston towards its release position shown. Onadmission of hydraulic pressure to chamber 66 the piston 64 advances toengage the brake.

An extension housing 71 bolted to the rear end of the converter-gearinghousing 12 houses both a transmission governor 72 and a speedometerdrive 74. These devices, which are driven by the transmission outputshaft 41, are conventional structures. The transmission output shaft 41in the vehicle installation is drivingly connected by a propeller shaftassembly and differential to the vehicles'driving wheels.

The hydraulically actuated friction drive establishing devices may beeither manually controlled and/or automatically controlled by ahydraulic control system whose valving is contained in a valve body 76located in a sump 78, the valve body and sump being secured to theunderside of the transmission housing 12. This hydraulic control systemmay be of any suitable conventional type and Describing now thetransmission operation that is available, when all of the friction driveestablishing devices are released the transmission is in neutral and nodrive is transmitted to transmission output shaft 41. When only bandbrake 49 is engaged and with sun gear 31 driven forwardly by converteroutput shaft 30, drive is transmitted from sun gear 31 through longpinion 32 to short pinion 34 which is in mesh with sun gear 43. Sincesun gear 43 is held stationary, short pinion 34 orbits forwardly aroundsun gear 43 to drive carrier 39 and connected transmission output shaft41 in the same direction as converter output shaft 30 (the forwarddirection) but at a reduced speed. This provides a low speed rangeforward drive between the transmissions input and output.

When only clutch 50 is engaged, sun gear 43 is locked to converteroutput shaft 30 and thus the range gearing is locked to provide a directdrive or 1:1 speed ratio between converter output shaft 30 andtransmission output shaft 41. This provides a high speed range forwarddrive between the transmissions input and output.

When only brake 61 is engaged, drive is transmitted from the converterdriven sun gear 31 via long pinion 32 to short pinion 34. Since shortpinion 34 is meshed with ring gear 60 which is being held, the shortpinion 34 walks around the ring gear in the reverse direction. Thiscauses carrier 39 and connected transmission output shaft 41 to turn inthe reverse direction but at a reduced speed with respect to theconverter output shaft 30 to provide a reverse drive between thetransmissions input and output.

According to the present invention, the single hydraulic pump 14provides the hydraulic pressure source for operating the transmissionand this pressure source may also be used to supply the vehicles otherhydraulically operated equipment. The hydraulic pump 14 is arrangedbetween the converter 10 and range gearing 11 and below thetransmissions centerline close to surnp 78.

- Referring to both FIGS. 1 and 2, the hydraulic pump \14 is aninternal-external gear type comprising an externally toothed drive gear81 eccentrically arranged within and in mesh with an internally tootheddriven gear 82, there being a crescent 84 arranged intermediate thesegears diametrically opposite the place where they mesh. The pump 14 issuitably ported to receive fluid from the transmission sump 78 on itsintake side and with the drive gear 81 supplied with power, it turns todrive the driven gear 82 to provide pumping action to deliver the intakefluid at pressure to suitable porting for delivery to operate thetransmission and other hydraulically operated vehicular equipment. Thefront side of flange 47 provides a face plate for the pumps gears which,together with crescent 84, are supported by a pump housing 86, the pumphousing being secured by the bolts 48 to the front side of flange 47.The pumps drive gear 81 is keyed to a drive shaft 88 extending parallelto the transmissions longitudinal central axis, shaft 88 being journaledin the front side 89 of pump housing 86.

Two pump drives are provided for driving the hydraulic pumps drive shaft88. One of these pump drives provides a one-way drive from thetransmission input to the pump and the other provides a one-way drivefrom the transmission output to the pump. The one-way pump drive fromthe transmission input comprises a one-way clutch 90 arranged betweenconverter 10 and a web 91 which is spaced from the forward side of pumphousing 86 by a spacer ring 92, web 91 and ring 92 being secured to thetrans mission housing 12 by bolts 48. The converter stators sleeve shaft28 extends through sleeve shaft 941 and is splined at its rear end tothe center of web 91 to provide reaction to the converters one-way brake24. As shown in FIGS. 1, 2 and 3, the one-way clutch 90 has an innerrace 93 keyed to the rear end of a sleeve shaft 94, shaft 94 beingwelded at its front end to the rear side of converter drum 16. The innerrace 93 of one-way clutch 90 is prevented from movement away from web 91by a reclutch 90 has external teeth 97 formed thereon meshing with teeth98 of a cluster gear 99 which is iournaled in web 91 and keyed to thepumps drive shaft 88. The oneway clutch 90 permits free forward rotationof the outer race 96 as indicated by the directional arrow in FIG. 3relative to the inner race 93 and connected transmission input andprevents reverse rotation relative thereto.

The one-way pump drive from the transmission output as shown in- FIGS. 1and 2 comprises a one-way clutch 100 trapped on one side by web 91 andthe rear end of sleeve shaft 94 and trapped on the other side by sleeve46. The one-way clutch 100 has an inner race keyed to an intermediateportion of converter output shaft 30. The outer race or cam ring 102 ofone-way clutch 100 has external teeth 104 formed thereon in mesh withteeth 105 of cluster gear 99. The one-way clutch 100 permits freeforward rotation of outer race 102 relative to the inner race 101 andconnected converter output shaft 30 and prevents reverse rotationrelative thereto.

The two pump drive gear trains 97- 98 and 104-105, preferably have thesame gear ratio. The one-way clutches 90 and I100 are conventional andmay be of either the roller type as best shown in FIG. 2 or of the spragtype.

With this pump drive arrangement, the hydraulic pump 14 is normallydriven through the one-way clutch '90 since the vehicles engine isnormally powering the transmission, recognizing that the converteroutput shaft 30 in this condition will always be rotating at a speedless than the transmission input. Since the transmission input isoverrunning the converter output shaft 30', the other one-way clutch 100overruns.

On the other hand, when the vehicle is in motion but the vehicle engineis not powering the transmission and with a transmission drive engaged,power is delivered from the vehicles driving Wheels to the converteroutput shaft 30 via the range gearing 11. In both the low speed andreverse speed transmission drive, the converter output shaft 30 willturn faster than the transmission output shaft 41 since in the reversepower flow direction these drives effect overdrive speed ratios, i.e.reciprocals of their reduction speed ratios. In the high speedtransmission drive the converter output shaft 30 turns at the same speedas the transmission output shaft 41 since there is then a 1:1 speedratio through the gearing. Under all of these drive conditions, theconverter output shaft 30' will turn forwardly relative to thetransmission input and at that time the other one-way clutch 100 willengage to provide drive to the hydraulic pump 14 with the one-way clutch90 then overrunning. Accordingly, the hydraulic pump 14 will run fasterto produce more pump how with either the low speed or reverse speedtransmission drive engaged as compared with pump operation with the highspeed transmission drive engaged.

Thus, the hydraulic pump 14 is driven by the transmission input when theinput is powering the transmission and is driven by the transmissionoutput when the output is powering the transmission. By having only onehydraulic pump with a drive from both the transmission input and thetransmission output, the advantages of a two-pump arrangement are gainedwith considerable cost savings. Furthermore, the single hydraulic pumpwith the two pump drives provides a very compact arrangementcharacterized by its short axial dimension and thus minimizes theoverall transmission length.

The above described preferred embodiment is illustrative of theinvention which may be modified within the scope of the appended claims.

I claim:

[1. In a vehicular transmission the combination of a transmission inputmember; a transmission output member; variable ratio drive means fordrivingly connecting said transmission input member to said transmissionoutput member; a hydraulic pump; drive means for normally drivinglyconnecting said transmission input member to said pump when saidtransmission input member is power-.

ing said variable ratio drive means; and additional drive means fordrivingly connecting said transmission output member to said pump onlywhen said transmission output member is powering said variable ratiodrive means] [2. In a vehicular transmission the combination of atransmission input member; a transmission output member; variable ratiodrive means for drivingly connecting said transmission input member tosaid transmission output member; a hydraulic pump; drive means fornormally drivingly connecting said transmission input member to saidpump when said transmission input member is powering said variable ratiodrive means; and additional drive means for overriding said firstmentioned drive means and drivingly connecting said transmission outputmember to said pump when said transmission output member is poweringsaid variable ratio drive means] [3. In a vehicular transmission thecombination of a transmission input member; a transmission outputmember; variable ratio drive means for drivingly connecting saidtransmission input member to said transmission output member; saidvariable ratio drive means including hydrodynamic means having animpeller powered by said input member and also having a turbine; aturbine output member driven by said turbine for powering saidtransmission output member; a hydraulic pump; drive means for normallydrivingly connecting said transmission input member to said pump whensaid transmission input member is powering said variable ratio drivemeans; and additional drive means for drivingly connecting one of saidoutput members to said pump only when said transmission output member ispowering said variable ratio drive means] [4. In a vehiculartransmission the combination of a hydrodynamic torque converter having aconverter input and a converter output; gearing means having a gearinginput powered by said converter output and also having a gearing outputand operable to selectively establish a plurality of different speedratio drives between said gearing input and output; a hydraulic pump;one-way drive means for connecting said converter input to drive saidpump in only one direction; and one-way drive means for connecting saidgearing input to drive said pump in said one direction whereby said pumpis normally driven by said converter input when said converter ispowering said gearing means and is driven by said gearing input whensaid gearing means is establishing a speed ratio drive and is powered bysaid gearing output] [5. In a vehicular transmission the combination ofan input member; an output member; a hydrodynamic torque converterpowered by said input member; gear means operable to selectivelyestablish different speed ratio drives between said converter and saidoutput member; a hydraulic pump arranged between said converter and saidgear means; pump drive means including oneway clutch means and gearmeans for normally establishing a one-way geared drive from said inputmember to said pump; and additional pump drive means including one-wayclutch means and gear means for establishing a one-way geared drive fromsaid output member through at least one of said speed ratio drives tosaid pump whereby said pump is driven by said input member when saidinput member is powering said converter and said pump is driven by saidoutput member when said output member is powering said gear means] 6. Ina vehicular transmission the combination of a transmission input member;a transmission output member, a hydrodynamic torque converter comprisingan impeller member connected to said transmission input member, aturbine member and a reaction member located intermediate the turbineand impeller members with all of said converter members cooperating toprovide a flow circuit for torque converter operation that effects ondrive of said impeller member by said ransmissi n input member drive ofsaid turbine member at speeds speed ratio drives between said turbinemember andsaid transmission output member to connect'said turbine mem-=ber to drive said transmission output member for normal transmissionoperation wherein turbine member speed never exceeds-the'speed of saidtransmission input mem ber and said impeller member and also to connect'said.

transmission output member. to drive said turbine m'emben faster thanthe speed of said impeller. member and' said transmission input member;'a-hydraulic pump-arrangedv between said converter and said gear means;pump drive means including one-way speed responsive clutch' meansarranged between said converter-and said 'pump jor drivingly connectingsaid transmission input mmber said pump by said one-way clutch meansengaging only when the speed of said transmission input memb'er'wouldotherwise exceed "the pump speed; and additional pump drive meansincluding one-way speed responsive-clutch: I

means arranged between said converter and said "pump for dri'vinglyConnecting said transmission output member otherwise exceed pump speed 3whereby saidpump' is driven by said transmission input member'only whensaid transmission input member'is delivering power to said converter andsaid pump is driven by said transmission Output member only when saidtransmission output member is delivering power to said gear means.

7. In a vehicular transmission the combination of-a housing; atransmission input member rotatably supported in said housing; atransmission output member rotatably supported in said housing; ahydrodynamic torque converter within said housing and comprising animpeller member connected to said transmission input member, a turbinemember and a reaction member located intermediate the turbine andimpeller members with all of said converter members cooperating toprovide a: flow circuit for torque converter operation that effects ondrive of said impeller member by said transmission input member drive ofsaid turbine member at speeds approachingbut never exceeding impellermember speed;

gear means within said housin operable to selectively. establishdifierent speed ratio drives between said turbine member fornormaltransmission operation wherein turbine member speed never exceeds thespeed of said transmission tnputmember and said impeller member andalso-'touconnectsaid transmission output member to. .drive said turbinemember faster than the speed of said impeller member and saidtransmission input member; a hydraulic pump within said housing andarranged between said converter and said gear means; pump drive meanswithin said housing and arranged between said .converter and said pumpand including one-way speed responsive clutch means for drivinglyconnectin said transmission input. member and said impeller member tosaid pump 'by' said one way clutch means engaging only when the speed ofsaid transmission input member and said impeller member would otherwiseexceed the pump speed; and additional .pump drive means within saidhousing :and arranged between said converter and said pump andincluding. one-way speed responsive clutch means f r drivinglyconnecting said transmission output member througlt -at least one ofsaid speed ratio drives to said pump-by the last-mentioned said one-wayclutch means engaging only when the speed of said turbine member whendriven-:b said transmission output member would otherwise exceed pumpspeed whereby said pump is drivenby -saidv transmission input memberwhen said 2,745,295 5/1956 Burnett 74 732 X 2,749,775 6 1956 Simpson 74731 3,033,353 6/1962 Roche 74 730 3,093,012 6/1963 Place 74677 3,394, 137/1968 Dhonau 74 731 FOREIGN PATENTS 737,400 6/1943 Germany 74-730ARTHUR T. MCKEON,'Primary Examiner member and. said transmission outputmember to connect us. (:1. x.R.

